1987 bronco 4.9 litres

[help me please]

hi guys last week my truck died 1987 bronco 4.9 litre no fuel going to the injectors replaced the relay the found a broken wire fixed it and no still no power going to fuel pump when i use my test light i turn the key on the lith goes on breifly then out i crank the motor over and the same thing i need help with this please

 

[jsomedaysoon]

that happened to me in my 88 one time. turned out i had accidently hit the fuel cut off switch. i just had to pop it back up and the truck started. allthough the next time it happend i needed a new fuel pump. point is i would check that little button first lol

 

[help me please]

thxs jsomedaysoon i will check that in the morning need beer rite now that dam truck is drive m crazy

 

[jsomedaysoon]

lol better get used to it. its usually a love hate relationship.

 

[92bronco_in_progress]

could be the fuel pump relay

 

[help me please]

thxs 92 bronco but i just put a new relay in and the little botton is good any more ideas would be great I dont like driving the jeep

 

[BroncoJoe19]

You'll have to back-track through the circuit to find out where you should have power, but don't and then keep following the circuit until you find that you do have power. When you discover that you have power, then the break in teh circuit is likely in the last length of wire, switch, or connector that you checked.

So I am thinking that in your circuit, you'll have the battery, then the fuse(s)? then the ignition switch, then the fuel inertia safety switch, then the fuel pump relays (there are two of them, one for each pump) then the pump(s) and associated grounds.

If I were doing this... the first place I would check for power is at the relays at the battery side of the big connectors. Then with the key ON at the big connector on the fuel pump side of the relay(s).

I'd start there because it is pretty much in the middle of the circuit, and is by far the easiest place to get to. One can do it standing up! /emoticons/[email protected] 2x" width="20" height="20" />

 

[BroncoJoe19]

Just a point of clarification... the fuel pump enertia switch button should be depressed, not up.

 

[jsomedaysoon]

Just a point of clarification... the fuel pump enertia switch button should be depressed, not up.

thanks... thats what i ment. its been almost ten years since i had that 88.

 

[help me please]

thxs guys got the truck running wire from high pressure pump was grounding out on my front drive shaft should be good till next problem ****

 

[Yardape]

Thats exactly what was happening on mine when I bought it. It actually fried the circut, I traced the wire on a wiring diagram and found out the yellow wire had no power, so I ran a power wire from the battery to the yellow wire and it fired up. drove it like that for 3 years.